39
Arc-flash hazard and hazardous voltages.
Will cause death, serious injury or property damage.
To avoid arc-flash burns or electrical shock, only qualified personnel
should work on or around this equipment after becoming thoroughly
familiar with all danger or warning notices, and procedures contained
herein. Personnel must observe all applicable regulations (e.g., OSHA),
follow all requirements of NFPA 70E and adhere to specific operating
procedures applicable to the installation. Use appropriate personal
protective equipment (PPE) for the voltage and arc-flash incident
energy exposure.
l
The ground and test device
then automatically closes,
opening the 52b contacts
driven by the major bell
crank of the device. The
52b contact 41-42 opens
the spring release coil
circuit, and 52b contact
51-52 opens the anti-
pump relay (52Y), spring
release coil and motor
circuits. This, in turn,
allows the anti-pump relay
to drop out. All spring
charging and spring
release circuits are open.
l
Contacts 52a 23-24 and
33-34 close in the tripping
circuit, which enables
tripping at a later time,
when the selector switch
is moved to the TRIP
position.
B1.4.8 The selector switch may now be
returned to the OFF position, and
padlocked or locked by key if
desired.
B1.4.9 An opening operation requires that
the selector switch be moved to the
TRIP (or OPEN) position. In this
position, depress the open
pushbutton, and observe that the
ground and test device opens.
Confirm the panel indicator shows
that the ground and test device
is open.
B1.4.10 The sequence allowed by the
control circuit is as follows:
l
Selector switch is in the TRIP
position:
l
Switch contacts TS/T 12-13
and TS/T 16-17 closed.
l
Contacts 52a 23-24 and 33-34
are closed if the ground and
test device is closed.
l
Depressing the open pushbutton
energizes the tripping solenoid
52T, opening the ground and
test device.
B1.5
Refer to the "Frame interlock"
description and confirm the
appropriate interference blocks are
mounted in the positions required
to allow the ground and test device
to be inserted into the chosen
compartment.
B2. System test procedures
It is imperative that the user become totally
familiar with every aspect of a ground and
test device before using it. The user must be
certain which primary circuits connect to
each primary disconnect (stud) and the user
must know if these circuits are or could be
energized due to backfeed. The user must
make certain that the primary circuit is
de-energized before performing any testing,
including testing for insulation resistance.
Make no assumptions and double check
each step!